... began early 1980.1)Items——membrane switch, keypad, membrane keypad, keyboard switch, switch panel, membrane panel, membrane overlay, ... 300g (2 - 10oz)f-2) Tactile type——150 - 400g (6 - 14oz.)g) Switch strokeg-1) Flat type 0.1 - ... 0.5mmg-2) Tactile type—— 0.6 - 1. ... type——5,000,000 closures or moreh-2) Tactile type——1,000,000 closures or morej) Surface ...